- buisje voor scheikundig onderzoek
- glass tube closed at one end
- 5. When the reaction is over, place the test-tube on a damp cloth.
- If you leave them lying on the desk they may roll off, so stand them in the test-tube rack.
- Test tube racks for baths
- Test tube stand for shakers
- Operation test of the (gas-tube) pressure relief valve
- Transfer about 10 ml of this extract to a test tube fitted with stopper.
- Dilute 1 ml of the solution with 1 ml of water in a small test tube.
- The test substance must not dissolve noticeably in, or react with, the U-tube fluid.
- Test portion Weigh 2,00 ± 0,001 g of test sample into a centrifuge tube (6.2) or suitable stoppered flask (50 ml).
- Incline the test tube, and carefully introduce down the side of the tube 2 ml of sulphuric acid so that it forms a lower layer.
- The test substance must not dissolve noticeably in, or react with, the U-tube fluid. A pressure gauge can be used instead of a U-tube (figure 3b).
- Weigh 1,0 g of the sample to the nearest 0,1g and transfer it into the test tube (4.3).
- The chosen test portion (6.3) is weighed into a centrifuge tube (5.3) and 50 ml 40 % ethanol (4.1) is added.
- Heat a few drops of the sample in a test tube with about 0,5 g of potassium bisulphate.
- Place 10 ml of this solution in a test tube (4.6) and add 10 ml of molybdovanadate reagent (3.6).